Theorem isorcl2 50241

Description: Reverse closure for isomorphism relations. (Contributed by Zhi Wang, 17-Nov-2025.)

Hypotheses

Ref	Expression
isorcl.i	⊢ 𝐼 = (Iso‘𝐶)
isorcl.f	⊢ (𝜑 → 𝐹 ∈ (𝑋𝐼𝑌))
isorcl2.b	⊢ 𝐵 = (Base‘𝐶)

Assertion

Ref	Expression
isorcl2	⊢ (𝜑 → (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵))

Proof of Theorem isorcl2

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		isorcl.f	. . 3 ⊢ (𝜑 → 𝐹 ∈ (𝑋𝐼𝑌))
2		isorcl2.b	. . . . 5 ⊢ 𝐵 = (Base‘𝐶)
3		eqid 2760	. . . . 5 ⊢ (Inv‘𝐶) = (Inv‘𝐶)
4		isorcl.i	. . . . . 6 ⊢ 𝐼 = (Iso‘𝐶)
5	4, 1	isorcl 50240	. . . . 5 ⊢ (𝜑 → 𝐶 ∈ Cat)
6	2, 3, 5, 4	isofval2 50239	. . . 4 ⊢ (𝜑 → 𝐼 = (𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦)))
7	6	oveqd 7437	. . 3 ⊢ (𝜑 → (𝑋𝐼𝑌) = (𝑋(𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦))𝑌))
8	1, 7	eleqtrd 2862	. 2 ⊢ (𝜑 → 𝐹 ∈ (𝑋(𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦))𝑌))
9		eqid 2760	. . 3 ⊢ (𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦)) = (𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦))
10	9	elmpocl 7662	. 2 ⊢ (𝐹 ∈ (𝑋(𝑥 ∈ 𝐵, 𝑦 ∈ 𝐵 ↦ dom (𝑥(Inv‘𝐶)𝑦))𝑌) → (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵))
11	8, 10	syl 18	1 ⊢ (𝜑 → (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   = wceq 1569   ∈ wcel 2144  dom cdm 5650  ‘cfv 6538  (class class class)co 7420   ∈ cmpo 7422  Basecbs 17392  Invcinv 17925  Isociso 17926

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732  ax-rep 5231  ax-sep 5248  ax-nul 5259  ax-pow 5326  ax-pr 5390  ax-un 7751

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-ral 3077  df-rex 3087  df-reu 3366  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3847  df-ss 3896  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-if 4482  df-pw 4558  df-sn 4585  df-pr 4587  df-op 4835  df-uni 4867  df-iun 4952  df-br 5103  df-opab 5167  df-mpt 5186  df-id 5545  df-xp 5656  df-rel 5657  df-cnv 5658  df-co 5659  df-dm 5660  df-rn 5661  df-res 5662  df-ima 5663  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545  df-fv 6546  df-ov 7423  df-oprab 7424  df-mpo 7425  df-1st 8001  df-2nd 8002  df-inv 17928  df-iso 17929

This theorem is used by:  isoval2  50242  catcisoi  50628